Dialkylaminoethyl diphenylmethylpiperidinepropionates



3,045,023 Patented July 17, 1962 United States Patent Diiice 3,045,023 DIALKYLAMINOETHYL DIPHENYLMETHYL- PIPERIDINEPROPIONATES Kurt J. Rorig, Glenview, IlL, as'signor to G. D. Searle & Co., Chicago, IlL, a corporation of Delaware No Drawing. Filed Apr. 6, 1960, Ser. No. 20,238

7 Claims. (Cl. 260-4943) This invention relates to dialkylaminoalkyl diphenylalkylpiperidiuealkanoates and processes for the manufac ture thereof. More particularly, this invention relates to chemical compounds of the formula wherein X represents hydrogen or a hydroxy radical, and

R represents an alkyl radical.

Among the alkyl radicals represented by R, especially lower alkyl radicals are preferred, which is to say methyl, ethyl, propyl, isopropyl, butyl, isobutyl, sec-butyl, tertbutyl, pentyl, isopentyl, tert-pentyl, neopentyl, hexyl, isohexyl, heptyl, octyl, and like C H radicals wherein n represents an integer amounting to less than 9.

Equivalent to the foregoing basic esters for purposes of this invention are corresponding acid addition salts, the formula of which is G we.

wherein X and R are defined as before; Q represents one,

- tory properties, and they appear to depress the central nervous system.

Manufacture of the basic esters hereof proceeds by heating an appropriate piperidine of the formula and dialkylaminoethyl acrylate of the formula in an inert solvent medium, the meanings of X and R in the formulas remaining as before. Con-version of the basic esters so produced to acid addition salts is accomplished by admixture with 1 or 2 equivalents of inorganic or strong organic acids, the anionic portions of which conform to Q as hereinabove set forth. The following examples describe in detail compounds illustrative of the present invention and methods which have been devised for their manufacture. However, the invention is not to be construed as limited thereby, either in spirit or in scope, since it will be apparent to those skilled in the art of organic synthesis that many modifications, both of materials and of methods, may be practiced without departing from the purpose and intent of this disclosure. Throughout the examples hereinafter set forth, temperatures are given in degrees centi-grade and relative amounts of materials in parts by weight, except as otherwise noted.

Example I Z-dimethylaminoethyl 4-(diphenylhydroxymethyl) 1- piperidinepropionate.-A solution of 134 parts of ot,a-dl phenyl-4-piperidinemethanol and 72 parts of Z-dimethylaminoethyl acrylate in 2500 parts of butanone is heated at the boiling point under reflux for 12 hours. The resultant solution is made just acid with hydrogen chloride dis solved in 2-propanol and then filtered. The filtrate is diluted with anhydrous ether to precipitate an oil. Supernatant solvent is decanted from the oil, which is thereupon mixed with an excess of aqueous sodium hydroxide. The mixture thus obtained is extracted with ether. The ether extract, dried over anhydrous sodium sulfate and stripped of solvent by vacuum distillation, affords Z-dimethylaniinoethyl 4-(diphenylhydroxymethyl)-1 piperidinepropionate as the residue, an oil' resistant to crystallization. The product has the formula Example 2 this point, 116 parts of maleic acid is introduced. Solvent is removed by decantation, and the residue is partitioned between ether and aqueous sodium hydroxide. To the ethereal phase, dried over solid potassium carbonate, is added sufiicient hydrogen bromide dissolved in absolute ethanol to make the resultant solution barely acid. The precipitate which forms is Z-diethylaminoethyl 4- (diphenylhydroxym'ethyl) 1 piperidinepropionate dihydrobro} mide, which, recovered on a filter and recrystallized from Example 3 2 diethylaminoethyl 3 (diphenylhydroxymethyl) 1- piperidinepropionate.-A solution of 134 parts of a,adiphenyl-3-piperidinemethanol and 86 parts of Z-diethylaminoethyl acrylate in 2500 parts of butanone is heated at the boiling point under reflux for 8 hours. There is then introduced 116 parts of maleic acid, precipitating an oil which is isolated by decantation of the supernatant solvent. The oil is partitioned between ether and aqueous sodium hydroxide; The ethereal phase, dried over solid potassium carbonate and stripped of solvent by vacuum distillation, alfords 2 diethylaminoethyl 3 (diphenylhydroxymethyl)-1-piperidinepropionate as the residue. The product has the formula Example 4 2dimethylaminoethyl 4-(diphenylmethyl)piperidine-lpropionate dihydr0chl0ride.-A solution of 126 parts of 4-(diphenylmethyl)piperidine and 72 parts of Z-dimethylaminoethyl acrylate in 2500 parts of butanone is heated at the boiling point under reflux for 12 hours. The resultant solution is made just acid by addition of hydrogen chloride dissolved in 2-propanol. The resultant mixture is filtered to remove unreacted starting material. The filtrate is warmed and diluted with anhydrous ether to the point of incipient turbidity. Upon standing and chilling, Z-dimethylaminoethyl 4-(diphenylmethyl) 1 piperidinepropionate dihydrochloride precipitates as a white powder which, recrystallized from a mixture of absolute ethanol and anhydrous ether, melts at 224-227". The product has the formula (IJHzCHaC O O CHaCHzN(CH5)2-2HCI W Example 5 2 diethylaminoethyl 4 (diphenylmethyl)piperidine-I- propionate dihydr0chl0ride.A solution of 126 parts of 4-(diphenylmethyl)piperidine and 86 parts of 2-diethylaminoethyl acrylate in 2500 parts of butanone is heated at the boiling point under reflux for 21 hours. The resultant mixture is filtered hot, and to the hot filtrate is added sufiicient 2-propanolic hydrogen chloride to effect A slight acidity. Upon standing, 2-diethylaminoethyl 4-(diphenylmethyl) l piperidinepropionate dihydrochloride precipitates as a white gel which, filtered olf and washed thoroughly with ether, melts at approximately 248-250.

5 The product has the formula What is claimed is: 1. A compound of the formula (311201120 0 O CH1CHzNRz (N EQ wherein X represents a member of the group consisting of i H and OH and R represents an alkyl radical, the formula thereof being 5 n 2n+1 wherein n represents a positive integer amounting to less than 9.

2. A compound of the formula (EHzCHzCO O CHzOHrNR: N i i wherein R represents an alkyl radical, the formula thereof being wherein n represents a positive integer amounting to less than 9.

3. A compound of the formula wherein R represents an alkyl radical, the formula thereof being n 2n+1 wherein n represents a positive integer amounting to less than 9.

4. 2-diethylaminoethyl 4 (diphenylhydroxymethyl)-1 7 piperidinepropionate.

5. A compound of vthe formula 'omorrzoooomcnmm wherein R represents an alkyl radical, the formula there- No references cited. 

1. A COMPOUND OF THE FORMULA 